Wednesday, September 17, 2014

A Short Break in the Clouds - StarLog 09/17/2014


While making the drive back to my apartment this morning I noticed a clear patch of sky so I made the quick decision to attempt a brief star gazing session.  Ever since I got my new pair of astronomy binoculars (Orion 25x100) I have been looking for breaks in the weather so I can try them out.  Unfortunately the clouds have been very persistent so far this September. 

I did not record the exact time of my observations but it was between 05:30:00 and 07:00:00 facing east.  Below is a screenshot taken from Stellarium of what the night sky would have looked like had there been clear skies.  I was only able to view a few dozen of the brightest stars.  



Screenshot taken from Stellarium of my view of the night sky.


A visual of the cloud cover that plagued my observations.


Orion's Belt (or the Belt of Orion)

 My first observation was of Orion’s belt or the Belt of Orion. The constellation consists of the three very bright stars, Alnitak, Alnilam and Mintaka. 

Alnitak is the lower of the three stars and is actually a multiple star system consisting of at least three stars, a possible 4th has not yet been confirmed! Source  Two stars define the axis of the triple star system.  The largest is a blue supergiant which is estimated to have a diameter that is 20 times that of our own Sun.  I added a size comparison that I took off of Wikipedia to help visualize this behemoth of a star, see below. Source The smaller axial star is a blue dwarf, while the third guy who makes up the triple star system is another blue dwarf and it takes him 1,500 years to orbit both his twin and the massive blue supergiant. 

Visual of Alnitak's blue supergiant star next to our own star, the Sun. Source

Alnilam is the central star in the constellation and is a blue supergiant.  What is so cool about this star is the sheer distance from us (Earth).  From our point of view the star is nearly as bright as the rest of Orion’s belt, but in fact Alnilam is nearly twice as far from our Sun as both Alnitak and Mintaka!  Because our ability to see an object in the night sky is dependent on the distance, the size and the luminosity this tells us that Alnilam is very, VERY bright!  It is also very massive, so large that it cannot contain itself and is losing mass around 20 times more rapidly than our own Sun.  This baby of a sun (four million years old) is expected to transition into a red supergiant and go critical (supernova) in the next few million years. Source
Mintaka is the northwestern most star and consists of a multiple star system.  The system contains a large blue giant and a larger white star.  Mintaka is the dimmest star in the constellation because the stellar system passes in front of itself in what is termed an eclipsing binary variable star.  Wikipedia tells me that this is when one star orbits in front of the other dimming the light from the system.  Source

Orion Nebula (Messier 42)
Moving south from Orion’s belt I made my way to the Orion Nebula or Messier 42.  This was my first experience with deep sky objects and I was not disappointed.  Although visually it just looked like a fuzzy faint cloud it was the awareness of what I was seeing that blew me away.  I was looking at the brightest, youngest and closest star-forming region to Earth.  The object consists of clouds of gas, dust and ionized volumes of more gas all of which are violently mixing to form thousands of new stars in what has been aptly dubbed, a stellar nursery. Source 
Orion Nebula as seen by Hubble.  Source
Orion Nebula through 6-inch refractor telescope, very similar to my view. Source


Moon
Full moon image from Nasa. Source
 
The view I resolved through the lens of my iphone 4S looking through one of the eyepieces of my Orion 25x100s.

The view as seen with my eye is significantly better and the binoculars provided a very crisp and clean image that I was very happy with.  I was able to see craters, mountains and could clearly depict topography on the surface of the moon. 

Something to think about when looking up at the moon is just how far out there in space it actually is.  It may look large compared to all the other objects, but it only covers a very small patch of the night sky.  So small in fact, that with your arm extended you can cover up the Moon with your pinky finger!  The image below helps you wrap your mind around the vast distance between Earth and the moon.  Within that distance all the planets of our solar system could fit!


  An image I got off the front page of Reddit a while back. 
Average distance between the Earth and the Moon with all the planets of our solar system contained between.

Jupiter

Image of Jupiter and two of the Galilean Satellites taken by Hubble.   

Image taken by anonymous amateur astronomer of Jupiter and all four Galilean Satellites.


Screenshot taken from Stellarium of Jupiter and its moons similar to my view.
 
The planet Jupiter is the fifth planet out from our Sun, and is regarded as a “gas giant”.  This is because it has no solid rocky surface like we have here on Earth.  Speaking of Earth, more than 1,000 Earths would fit inside the volume of Jupiter!

Another interesting fact that I find especially fascinating about this planet is that it has the shortest day of all the planets: 9 hours and 55 minutes.  This spin is so fast that it flattens Jupiter at the poles and gives the planet an oblate shape. Source

Quick thought experiment.  Image that Jupiter did have a solid surface and you were standing on it.  Then imagine that suddenly Jupiter stopped rotating, instantly.  You would find yourself hurtling through the atmosphere of Jupiter at over 28,000 mph or roughly 19 times as fast as an F-16 fighter jet!

Because Jupiter is so large its gravitational pull attracts a lot of stuff.  The planet has a thin ring system and 67 known moons!  I was able to see four, the Galilean Satellites: Io, Europa, Ganymede and Callisto.  Europa is of particular interest to the scientific community because it has a large ocean beneath its icy surface. Here on Earth where there is water there is life, which leads one to speculate about what might be swimming around beneath the surface of Europa.


NASA images of the Galilean Satellites: Io, Europa, Ganymede and Callisto.

Despite poor visibility I am pleased with what I was able to observe.  I find that the most enjoyable part of looking up is trying to wrap my head around what it is exactly that I am looking at.  The experience is both incredibly exciting and humbling at the same time.  After all we are all just riding through space on a pale blue dot...
 
Carl Sagan - Pale Blue Dot


 











 

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